Mill for grinding paints, enamels, inks, and other viscous substances



MILL FOR GRINDING WXINTS, ENAMELS, INKS AND OTHER VISGOUS SUBSTANCES Filed; Nov. 27, 1939 Patented Mar. 25, 1941 UNITED STATES BULL FOR GRINDING PAINTS, ENAMELS, INKS, AND OTHER VISCOUS SUBSTANCES William Thompson Forsyth, Whitecraigs,

Seat] and Application November 27, 1939, Serial No. 306,240 In Great Britain September 28, 1938 3 Claims.

This invention refers to improvements in and relating to mills for grinding paints, enamels, inks and other viscous substances wherein a grinding block is pressed forcibly into contact with the periphery of a single rotating roller so as to grind the material in its passage between the periphery of the roller and the grinding block.

According to this invention, the mill is provided with two relatively displaceable grinding blocks mounted in a housing with a narrow channel between the adjacent faces of the blocks, said channel extending nearly the full length of the blocks and vertically from the periphery of the roller to the outer ends of the blocks. Preferably one or more filtering devices is or are provided to filter the ground material.

In one form of construction, a filtering device is mounted in the blocks at a point intermediate the height thereof and extending across the channel between the blocks.

In another form of construction, a filtering device is mounted in a chamber in the housing at the ends of the blocks remote from the roller, the housing being provided with a perforated 5 cover through which the filtered material passes to a chute, from which it is drawn off as required.

The channel between the blocks may be formed by suitably recessing either or both of the contacting faces of the blocks.

The invention is illustrated in the accompanying drawing, in which:

Fig. 1 shows part of a grinding mill with one form of this invention applied thereto;

Fig. 2 is an elevation of the grinding blocks of Fig. 1; and

Fig. 3 is a partly sectional end elevation of a mill provided with two grinding members arranged diagonally opposite to each other; and

Fig. 4 is an elevation view of the housing shown in section in Fig. 3.

As illustrated in Figs. 1 and 2, the roller I has in contact with its periphery two blocks 2, 3, which are mountedin a housing (not shown) and 45 have between them thechannel 4. This channel 4 is formed by suitably recessing both the adjacent faces of the blocks 2, 3, as clearly seen in Fig. 2. This channel extends to near the ends of the blocks, where the adjacent faces of the 50 blocks are in contact to seal oil the channel I and prevent the material escaping sideways from the channel 4. The seals also prevent any material, which may escape laterally under the edges of the hopper, from being carried, with the re- 55 fined material, up the passage between the blocks.

In order that the ground material, after passing between the periphery of the roller and the grinding block 2, may be forced up the channel 4, the pressure per unit area of contact with the roller I of the block 3 must exceed the pressure per unit area of contact with the roller I of the block 2. This is effected by suitably adjusting the pressure screws (not shown), in the present case so that the pressure on the block 3 is greater than that on the block 2.

The material to be ground is fed on to the periphery of the roller I from a hopper at a point just in front of the grinding block 2, and is carried by the rotation of the roller under the block 2. When the material reaches the channel I, it is forced thereinto and passes up through said channel, through the pad of filtering material 5 to the outlet end of the channel into the housing of the grinding blocks, from which it is drawn as and when required.

In the construction shown in Figs. 3 and 4, the roller I, which is mounted in a cylinder I3, supported by a base It and provided with a hopper I5, also has two blocks 2, 3, in contact therewith, mounted in a housing 6, and forced into contact with the periphery of the roller I by means of the pressure screws i'l'. At a point intermediate the height of the blocks 2, 3, each is recessed to accommodate a pad 5 of any suitable filtering material, and an additional filtering device is mounted in a chamber of the housing at the outer ends of the grinding blocks.

The housing 6 is provided with a perforated, recessed cover I, secured in position on the housing by bolts 8, 8. Clamped between the housing 6 and the cover 1 is the filtering device, consist ing, preferably, of a piece of gauze 9 to the rear of which is secured a pad of felt, or other suitable .additional filtering material, Ill. The perforations I I in the cover I discharge the filtered material into a chute I2, from which it is drawn as required. 7

In this form the channel 4 is shown as being formed by recessing only the block 2, and the block 3 is shown as being of smaller size than the block 2. Consequently, therefore, the pressure will be applied uniformly to both blocks, by the pressure screws I1, so that the pressure per unit area on block 3 is greater than that on block 2.

I claim:

l. A mill for grinding paints, enamels, inks and other viscous substances, comprising a stationary cylinder supported upon a base plate, a hopper integral with said cylinder, a grinding roller rotatably mounted in said cylinder, a housing in said cylinder, two relatively dispiaceable grinding blocks mounted in said housing with their grinding faces bearing against the grinding roller and a substantially narrow channel for discharge of the ground material between adjacent faces of said blocks which extend nearly the full length of the blocks and transversely from the inner face to the outer end of the blocks, screw means for adjusting the pressure on the blocks so that the pressure per unit area of contact of the second block with the periphery of the grinding roller is greater than the pressure per unit area of contact of the first block with the periphery of said roller and at least one filtering device extending across the narrow channel in said grinding blocks adapted to filter the ground material.

2. A mill for grinding paints, enamels, inks and other viscous substances, comprising a stationary cylinder supported upon a base plate, a, hopper integral with said cylinder, a grinding roller rotatably mounted in said cylinder, a housing in said cylinder, two relatively displaceable grinding blocks mounted in said housing with their grinding faces bearing against the grinding roller and a shallow recess in adjacent faces of the blocks forming a substantially narrow channel which extends nearly the full length of the blocks and transversely from the inner face to the outer end of the blocks, screw means for adjusting the pressure on the blocks so that the pressure per unit area of contact of the second block with the periphery of the grinding roller is greater than the pressure per unit area of contact of the first block with the periphery of said roller and at least one filtering device extending across the narrow channel in said grinding blocks adapted to filter the ground material.

3. A mill for grinding paints, enamels, inks and other viscous substances, comprising a stationary cylinder supported upon a base plate, a hopper integral with said cylinder, a grinding roller rotatably mounted in said cylinder, a housing in the cylinder, two relatively displaceable grinding blocks mounted in said housing with their grinding faces bearing against the grinding roller and a shallow recess in the adjacent face of one of the blocks forming a substantially narrow channel which extend nearly the full length of the block and transversely from the inner face to the outer end of said block, a perforated cover secured to said housing over the outer face of the grinding blocks, at least one filtering device interposed between the grinding blocks and perforated cover, and screw means associated with said grinding blocks for adjusting the pressure on the blocks so that the pressure per unit area of contact of the second block with the periphery of the grinding roller is greater than the pressure per unit area of contact of the first block with the periphery of said roller.

W. '1. FORSYTH. 

